Photographic color scanning apparatus



Fell 7, 1967 H. JAFFE ETAI.

PHOTOGRAPHIC COLOR SCANNING APPARATUS 2 Sheets-Sheet l Filed April 2'?,1964 HEM/2v L. Jar/re 12a/ PH M.. Da/ws INVENTORS ATTOQNEVS Peb- 7, 1957H. L.. JAFFE ETAL PHOTOGRAPHIC COLOR SCANNING APPARATUS 2 Sheets-Sheet 2Filed April 27, 1964 HENRY L. Jisp-FE E400/L4 M. Aon/ws INVENTORS ATTOENEVS United States Patent() 3,303,508 PHGTOGRAPHC CLR SCANNINGAPPARATUS Henry L. latte, Santa Monica, and Ralph M. Adams, San Gabriel,Calif., assignors to Cedars of Lebanon-Mt. Sinai Hospitals of the LosAngeles Jewish Medical Center, Los Angeles, Calif., a Californianon-profit corporation Filed Apr. 27, 1964, Ser. No. 362,747 27 Claims.l; (Cl. 346-33) This invention relates to nuclear medicine, andparticularly to diagnoistic techniques involving the distribution ofradioactive isotopes. By such means, malformations or malfunctions ofhuman organs may be detected.

In order to record the distribution of radioactive isotopes, certaindevices have heretofore been proposed and used. In one known device, aradiation detector is mounted for controlled traverses along a certainarea of the body corresponding to the location of the subject organ. Astylus carrying an arcing device, movable with but remote from thedetector, correspondingly traverses along paper. A black spot isproduced when the arcing device is operated. The arcing device isoperated periodically at a frequency corresponding to the intensity ofradiation. Accordingly, a graph is produced comprising a large number ofblack spots, with the concentration of spots corresponding to theconcentration of radioactive material. A graph of this character is noteasy to read or analyze. In -order to learn something signicant, thenumber of spots within a given area should be counted. In conjunctionwith such device there may be used a black and white film exposed by alight source that traverses with the detector. A photoscan in shades ofgray is produced. Small charges in radioisotope concentrations are noteasily perceived.

Recently there has been proposed a scanning system in which a graph ismade by producing impressions through a composite multi-color ribbon,together with a servo mechanism for correlating operative ribbon colorwith intensity of radiation. The printing head or the paper bed moveswith the traversing detector structure. The graph produced can then bemore readily comprehended, the intense concentration areas being coloredred, and the less intense concentration areas being colored, forexample, orange, yellow, green, blue, violet.

- The printing mechanism is quite noisy and considerably distracts andannoys the patient. It is then ditcult to keep the patient immobilizedfor possibly a considerable period of time while the scanning is inprogress. According, one object of this invention is to provide improvedcolor scanning apparatus that is noiseless. For this purpose, the imageis made photographically.

Another object of this invention is to provide a system of thischaracter than can be implemented largely by standard components, and atreasonable cost. Particularly, it is an object of this invention make itpossible to use an inexpensive color lilm pack of the Polaroid type sothat a color scan can be obtained immediately.

Still another object of this invention is to provide apparatus of thischaracter that can be installed on known scanning devices without in anyway disturbing the function of such apparatus. There is commerciallyavailable, for example, a scanner made by Picker X-ray Corp.,

of White Plains, New York, and having (l) a pulsev height analyzer fordetecting pulses of a characteristic amplitude corresponding to aselected isotope; (2) a rate meter incorporating suitable integrationcircuits for producing a signal for indicating the counting rate; and(3) a head upon which the radiation detector is mounted and which iscapable of controlled traverse in a rectangular coordinate system. Inorder to accomplish the installation, it is merely necessary to link thetraversing 3,303,508 Patented Feb. 7, 1967 ICC detector to apotentiometer system and to derive signals from the rate meter and theanalyzer.

Various organs of the body may be intelligently studied by scanningtechniques. But some organs are much larger than others. Accordingly, itis desirable, from the standpoint of economy of operation and from thestandpoint of convenience, to be able to reduce the image size so thatsmall photographic iilm or paper may be used. It is thus an object ofthis invention to provide apparatus in which image reduction may beeasily accomplished. For this and other purposes, use is made of anoscilloscope for producing a traversing light beam.

Another object of this invention is to provide a simple auxiliarycontrol for marking the iilm so that the relative position of thephysical anatomy can be located. Thus for example, a line correspondingto the lower edge of the right side of the rib cage may be superimposedin order to locate the position of the liver of a subject.

Still another object of this invention is to provide v apparatus of thischaracter having simple controls.

This invention possesses many other advantages, and has other -objectswhich may be made more clearly apparent from a consideration of oneembodiment of the invention. For this purpose, there is shown a form inthe drawings accompanying and forming a part of the presentspecification. This form will now be described in detail, illustratingthe general principles of the invention; but it is to be understood thatthis detailed description is not to be taken in a limiting sense, sincethe scope of this invention is best defined by the appended claims.

Referring to the drawings:

FIGURE l is a diagrammatic View of a color scanning system incorporatingthe present invention; and

FIG. 2 is a diagrammatic view of a typical variable width square wavegenerator usable in the system. In FIG. 1 there is diagrammaticallyillustrated a scanning device 10. A radiation sensing element ordetector 11 mounted at the end of a movable support or beam 12 may bepostioned above an examining table 13. Suitable tracking devicecontrols, and motor drives incorporated in the unit 10 cause thedetector 11 to traverse in a horizontal plane to scan emitted radiation.Adjustable limit switches localize the area of the scan. In the presentinstance, the detector traverses in a rectangular coordinate system. Forpurposes of discussion, the x direction maybe considered horizontal ortransverse to the height of the subject, and the y direction may beconsidered vertical, or along the height of the subject.

'Ilhe unit 10 incorporates an analyzer 14 .and a rate meter 15. Theanalyzer 14 is designed to iilter out all radiation except that causedby the isotope used in the study. For example, the analyzer may becapable of discriminating by analysis of pulse height. The analyzer 14is fed by the detector 11, as indicated by the lead 16.

The `output from the analyzer 14 is in the form of a train of pulses,the pulse being indicated in the circle 17 adjacent the output lead 18of the analyzer. The pulse at 17 has a constant amplitude, for example,of one volt and a constant pulse width, for example, of a half amicrosecond. The pulses as at 17 recur at a rate directly proportionalto the radiation of the selected isotope detected by the sensing element11.

The rate meter 15 integrates or accumulates the output of the analyzer17 on a time basis in order to provide a measure of the intensity ofradiation that can be conveniently displayed as by a dial 19.

The unit may incorporate in its housing a known color scanning devicethat produces vari-colored dots. For example, the arm or beam 12 may beconnected to a o printing head (not shown) that traverses along a paperbed mounted inside the apparatus 10.

By the aid of the apparatus diagrammatically illustrated in FIG. 1 aphotographic color scan is also produced without interference with theoperation of the unit 10. A camera photographs the screen of a cathoderay oscilloscope 21. The camera image is registered on film contained ina Polaroid or similar film pack adapter 22.

The beam of the cathode ray oscilloscope is positioned in accordancewith the position .of the detector 11 and in a manner hereinafter to bedescribed. Furthermore the beam is in the form of a series of pulses,there being a pulse produced whenever a pulse is produced at theanalyzer output lead 1S. Hence the film exposure is directlyproportional to radiation.

The color of the camera image is also determined by t-he intensity ofradiation to facilitate reading of the picture produced. For thispurpose, ia series of filters 23 are provided that are contiguouslymounted on a common movable support 124.

The various filters 23 are interposed between the screen 24 of thecathode ray oscilloscope 21 and the lens of the camera 20. To ensureproper response, the screen 24 has a Wide band of spectral emission. Theiilters are preferably arranged in a series corresponding to the visiblespectrum with a red filter at .one end and a violet filter at the other.The filters in sequence may be red, orange, yellow, green, blue andshades of violet.

The red filter is operatively positioned at maximum radiation levels andthe violet filters are positioned at minimum radiation levels. For thispurpose the filter support 124 is positioned by the aid of a servomechanism` 25. The servo mechanism may be a standard article of commercehaving an output shaft 26 positioned in accordance with amplitude of adirect current voltage :applied to the input lead 27. Conveniently asuitable signal is available from the output ofthe rate meter 15.

A knob 28 in the balance circuit of the servo mechanism provides anadjustment of the excursion of the output shaft 26. For purposes ofCalibrating, the detector 11 is located at the position of maximumradioactivity and' the knob 28 adjusted so that the red filter is theninterposed between the camera and the oscilloscope screen.

In order to position the oscilloscope beam, signals are derived inaccordance with the x and y coordinates of the detector sensing head.For this purpose an x potentiometer 29 and a y potentiometer 30 areprovided. Potentiometers 29 and 30 are similar and are of a typecornmercially available, for example from the Helipot Division ofBeckman Instruments Company. The x and y potentiometers 29 and 30 areidentical.

The x potentiometer 29 comprises a pair of potentiometer resistors 31and 32 having sliders 33 and 34 respectively engageable with theresistors 31 and 32. The sliders are connected together for movement inunison by an input shaft 9. 'Ihe input shaft is directly linked orgeared to the support 12 or the detector so that the sliders 33 and 34are at corresponding ends of the resistors 31 and 32 when the detectoris at one limit of its movement in the x direction. Correspondingly theslide-rs 33 and 34 are at the opposite corresponding ends of therresistors 31 and 32 when the detector 11 is at the other limit of itsmovement in the x direction. When the limit switches of the unit 10 areset to localize lthe area of scan, the sliders 33, 34 correspondinglymove over only a corresponding portion of the resistors 31, 32.

One end of the potentiometer resistor 31 and the opposite end of thepotentiometer resistor 32 are a negative potential -50 v. whereas theother end of the resistor 31 and the opposite end of the resistor 32 areat an positive potential +200 v. These valves are chosen with referenceto oscilloscope characteristics. Accordingly the potential differencebetween the slide-rs 33 and 34 may be varied from 250 v. to +250 v. withzero potential difference existing when the sliders are at a centralPQSQI: This potential diffe-rence, adjusted in a manner hereinafter tobe described, is applied across the horizontal plates 35 and 36 of theosccilloscope 21, and the beam is appropriately positioned.

The y potentiometer 30 similarly has a pair of resistors 37 and 38cooperable with sliders 39 and 40 operated in unison by an input shaft41. The input shaft 41 is directly coupled to the support 12 so as tocause movement of the shaft directly in accordance with the y positionof the detector 11. A suitable potential is applied to the resistors 37and 33 so that a direct current signal from -100 v. to |l00 v. isobtained in accordance with the position of the sliders 39 and 4e. Thesliders 39 and 40 have an excursion from one end of the correspondingresistors to the other as the detector 11 correspondingly travelsbetween its limits of its movement in the y direction. As the traverseof the detector is conlined by setting of limit switches, the sliders 39and 40 traverse along limited portions of the resistors 37 and 33.

The range of potential difference produced by the excursion of thepotentiometer sliders depends upon the extent of permitted traverse ofthe detector 11. This in turn depends upon the dimensions of the organunder study and the adjusted traverse of the detector. An image ratiocontrol circuit 44 makes it possible proportionately to Iadjust thesignals from the x and y potentiometers so that the oscilloscope beamfills the screen in any case. The image ratio control circuit 44includes two potentiometers 45 and 46 respectively for scaling thevoltage derived from the potentiometers 29 and 30. The potentiometer 45has two potentiometer resistors 47 and 48 connected together atcorresponding ends by a fixed resistor 49 to forni a voltage divider.The other ends of the resistors 47 and 48 are connected respectively tothe sliders of the x potentiometer 29. Cooperable with the resistors 47and 43 are ganged sliders 50 and 51 from which the output from the imageratio control 44 is derived. When the sliders 50 and 51 are at the lefthand ends of the potentiometer resistors 47 and 48 the full voltage fromthe potentiometer 29 is applied across the sliders 50 and 51. This maybe appropriate when the organ under study is small. When the sliders 50and 51 are moved to the right hand ends of the potentiometer resistors47 and 48, the signal voltage produced across the sliders 50 and 51 isproportionately reduced. Such setting may -be appropriate when a largeorgan is under study. In practice the resistors 47 and 43 have a valueof approximately 41/2 times that of the fixed resistor 49. Accordinglythe ratio of image reduction ymay be changed from 1:1 to 10:1 throughouta continuous range. A dial associated with the sliders may indicate theimage ratio.

The potentiometer 46 similarly comprisesresistors 54 and 55 cooperablewith sliders 56 and 57 are gange/i for movement in unison with thesliders 50 and 51. A fixed resistor 5S determines the limit to the imagereduction ratio.

The center of the organ to be scanned -ordinarily is not in the centerin the field of traverse of the detector head 11. It is not alwaysconvenient to position the subject so that the organ under study isdirectly in the center of the field of traverse of the detector 11.Accordingly when the detector 11 is Imoved to the position correspondingto the center of the organ the oscilloscope beam will ordinarily be awayfrom the center of the screen 24 since the sliders 39-40` and 33-34 willnot be centered. For this purpose, an image centering control 59 isprovided.

The image centering control, in effect, superimposes an adjustable biasupon the x and y signa-ls so that the beam is centered on the screen 24when the detector 11 is centered over the organ to be studied eventhough the center of the organ may not correspond to the center of thex-y range of movement of the detector 11.

The image centering control 59 includes a pair of potentiometers `60 and`61 respectively for the x signal, and

the y signal. The potentiometer `60 includes a pair of potentiometerresistors `62 and 63 cooperable with ganged sliders `64 and '65. Abattery 66 is connected across both potentiometer resistors 62 and 63but in opposite polarity. At the central position there is no potentialdifference between the sliders. Upon movement of the sliders 64 and 65to the left, the slider `65 becomes positive relative to the slider 64in accordance with the extent of slider movement. Similarly uponmovement of the sliders `64 and 65 to the right, the slider 65 becomesnegative relative tothe slider 6d.

The potentiometer sliders `64 and 65 are serially ins'erted between oneof the output sliders 50 of the x image ratio control and one of thehorizontal plates 36. Thus a lead 67 connects slider 50 to slider 64 anda lead 68 connects slider 65 to plate 36. The other output slider 51 ofthe x image ratio control is directly connected by a lead 69 to theother horizontal plate 35. When the centering potentiometer 60 is in acentral position, no bias is imposed upon the signal from the x imageratio control, but by adjustment of the sliders y64 and `65, a positiveor negative bias m-ay be imposed and in an amount adequate to center theoscilloscope beam when the detector 11 is in the center of its selectedlimited field of traverse.

The potentiometer 61 for the y signal is equivalent. Thus a lead 70directly connects the slider 56 from the y image ratio control to aslider 71 in turn cooperable with la potentiometer resistor 72. Slider73 cooperable with la companion potentiometer resistor 74 connects vialead 76 to one of the vertical plates 43. The other slider 57 from the yimage ratio controlconnects by a lead 77 to the other vertical plate 4Z.A battery 78 imposes a. suitable potential across the resistors 72 and74. The sliders 71 and 73 are ganged for joint movement and when movedin one direction, namely, to the left, a positive bias is imposed, andwhen moved to the right, a negative bias is imposed. Vertical centeringis thus achieved.

The unit may be of a type to cause the detector 11 to traverse alonglines parallel to the x axis, successive lines being spaced from eachother by an increment Ay. The -beam produced by the cathode ray tube 21desirably I'ills the space corresponding to successive horizontal linesin order to provide an appropriate image without discontinuity. For thispurpose, a saw tooth generator 80 is provided. The saw tooth generatormay produce a signal having a frequency that is high relative to therate of traverse of the detector so that the resulting trace lines areindistinct. A kilocycle signal is easily obtained for this purpose lby agenerator $0. The generator. 80 is coupled to one of the vertical plates43 through a coupling condenser S1. The amplitude of the generatedsignal may be controlled by an adjustable knob 82 that suitably varies acircuit element, such as a potentiometer. The height of the beam canthus be accurately controlled according to other variables.

The lens of the camera 20 is opened while scanning is in progress. Inorder to control iilm exposure, the beam intensity is controlled. Thisis necessary due to differences in radioisotope concentration imageratio, and scanning speed. For this purpose, a one shot square wavegenerator l83 is provided. The output lead 18 from the analyzer 14 isapplied to the input of the square wave generator 83 via contact S4 andan arm 85 of a selector switch 86. Thus the lead 18 connects to thecontact 8d and the arm S5 connects by a lead 87 to the input of thesquare wave generator '33. The generator 83 produces a pulse every timea pulse is applied thereto. The one shot generator 83 amplifies thewidth and height of the input signal, the width lbeing adjustable -by aselector switch 89. The one shot generator drives the grid 8E of theoscilloscope '21. The grid S8 of course gates the beam. The beam is onfor a time corresponding to the width of the pulse; hence, the wider thepulse, the longer the on time of the beam, and the greater the filmexposure. As indicated by the circle 90, the output wave form from theone shot generator may have an amplitude of 10 volts and an adjustablewidth ranging, say, from 2 to 6000 micro-seconds. Preferably theselector switch 89 has a substantial number of individual positionscorresponding to various on times of the beam. On times of 2, 3, 4, 6,8, 12, 18, 25, 50, 75, 100, 150, 200, 300, 400, 600, 800, 1,000, 1,500,2,000, 3,000, 4,000, 6,000 micro-seconds are adequate for properservice.

The one shot generator is in the form of a typical monostablemultivibrator as illustrated in FG. 2. The square wave generator has atransistor inverter amplier 91 and transistors 92 and 93 forming theoperative elements of the monostable multivibrator. The circuitcorresponds to that published for example in the General ElectricTransistor Manual. The pulse width depends upon the Value of capacitanceinserted between terminals 94 and 95. The selector switch S9 connectedacross the terminals 94 and 95 is capable of inserting the appropriatecondensers into the circuit. In the present instance only l2 condensersare illustrated.

For purposes of operation the patient is suitably irnmobilized under thedetector 11. The detector is centered at the desired area. The imagecentering control 59 is adjusted so that the beam is at the center ofthe screen. The traverse of the detector 11 is determined and the imageratio control is adjusted correspondingly. The saw tooth generator 80 isthen set so that the scan lines merge. The servo mechanism 25 is thenadjusted with the detector 11 over the area of maximum radioactivity sothat the red filter is positioned over the lens. Next the beam on timeis controlled by operation of the selector switch 89 in accordance withthe other conditions so as to produce suitable exposure. Scanning isthen started `at one corner of the eld and the shutter of the camera 20is opened.

`Preferably the camera includes a window so that the progress of theelectron beam may be viewed during the scan.

After the scanning has taken place the shutter is closed. Before the lmis developed it may be desirable to mark the iilm so as to locate theposition of the subjects anatomy, as for example the center of thesternum or the lower edge of the rib cage etc. For this purpose there isprovided a circuit associated with the selector switch 86. This circuitprovides an alternate manually controlled input to the one shot squarewave generator '33. This marking circuit includes a condenser 91 that isnormally charged through a charging resistor 92. Thus one side of thecharging resistor 92 connects to a source terminal 93. The other side ofthe resistor 92 connects to one side of the condenser 91. The other sideof the condenser connects to the ground terminal 95. An arm 96 of theselector switch connects to the junction `between the resistor 92 andcondenser 91. The arm 96 is coupled to the arm 85. When the selectorswitch 86 is in the full line No. 1 scan position illustrated the arm 96is idle and the condenser 91 approaches the potential ot the sourceterminal 93. When the selector switch is moved to the dotted line No. 3mark position, condenser 91 is discharged so as to provide an inputsignal to the square wave generator 83. Thus in this No. 3 mark positionthe arm 96 connects the condenser 91 toa discharge circuit. Thedischarge circuit includes an input resistor 97 for the square wavegenerator 83 of relatively small value, and a load resistor 95. Thus thecontact 99 engaged by the arm 95 connects to one side of the resistor98. The other side of the resistor connects to one side of the inputresistor 97, the other side of the input resistor being grounded. Thejunction between 93 and 97 is connected to the lead 87 and the input tothe one shot generator 83.

A pulse of current is accordingly applied and the square wave generator83 produces a pulse.

When it is desired to spot the film following the scan, the selectorswitch Se is moved to the No. 2 oit position and the selector switch 89is adjusted to an appropriate on time, usually ranging from 1000 to 6000microseconds. The camera shutter is opened. The detector lll. is movedalong a line corresponding to the signicant anatomical feature andduring the course of such movement the selector switch is repeatedlymoved to the No. 3 or mark position. A spring returning the switch 86from the mark to the off position assists the operation.

Finally the camera shutter is closed and the film from the pack 22 ispulled allowing the appropriate development time. The completed colorscan is then available.

The inventors claim:

1. In photographic color scanning apparatus cooperable with a detectorand a traversing mechanism for the detector: a holder for aphotosensitive sheet; means fixed with respect to the holder forproducing a spot of illumination on the sheet; means coupled to thedetector for causing the illumination spot to trave-rse relative to thephotosensitive sheet in accordance with the traverse of said detector;and means having preselected color coded characteristics interposedbetween the illumination producing means and the holder for changing the'color characteristic of the illumination spot in accordance with theactivity of the detector.

2. In photographic color scanning apparatus as set forth in `claim Itogether with means for changing the effective intensity of the spot inaccordance with the activity of said detector.

3. In photographic color scanning apparatus :cooperable with a detectorand a traversing mechanism for the detector: an oscilloscope having awide spectral "emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a signal to the vertical and horizontal deflectionmeans in accordance with the position of the detector; graded filtermeans mounted for interposition between the camera means and the screenfor effectively altering the spectral characteristic of the imageproduced by the camera means; and means for positioning the lter meansin accordance with the activity of the detector.

4. In photographic color scanning apparatus coperable with a detectorand a traversing mechanism for the detector: an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a signal to the vertical and horizontal deectionmeans in accordance with the position of the detector; adjustable biasmeans for producing signals for causing the oscilloscope beam to becentered on the screen when the detector is off center; graded filtermeans mounted for interposition between the camera means and the screenfor effectively altering the spectral characteristic of the imageproduced by the camera means; and means for positioning the filter meansin accordance with the activity of the detector.

5. In photographic color scanning apparatus cooperable with a detectorand a traversing mechanism for the derector: an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a signal to the vertical and horizontal deliectionmeans in accordance with the position of the detector; adjustable meansfor scaling said signal applying means for adjusting image size inaccordance with the area scanned by said detector; graded filter meansmounted for interposition between the camera means and the screen foreffectively altering the spectral characteristic of the image producedby the camera means; and means for positioning the filter means inaccordance with the activity of the detector.

6. In photographic color scanning apparatus cooperable with a detectorand a traversing mechanism for the detector: an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a signal to the vertical and horizontal defiectionmeans in accordance with the position of the detector; adjustable biasmeans for producing signals for causing the oscilloscope beam to becentered on the screen when the dete-ctor is oif center; adjustablemeans for scaling said signal applying means for adjusting image `sizein accordance with the area scanned by said detector; graded filtermeans mounted for interposition between the camera means and the screenfor effectively altering the spectral characteristic of the imageproduced by the camera means; and means for positioning the filter meansin accordance with the activity of the detector.

7. In photographic color scanning apparatus cooperable with a detectorand; a traversing mechanism for the detector: an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a signal to the vertical and horizontal deflectionmeans in accordance with the position of the detector; graded filtermeans mounted for interposition between the camera means and the screenfor effectively altering the spectral characteristic of the imageproduced by the camera means; means for positioning the filter means inaccordance with the activity of the detector; and means for producingelectrical pulses at a frequency corresponding to the activity of saiddetector; said oscilloscope having a gating electrode for controllingsaid beam and operated by said pulses.

S. In photographic color scanning apparatus cooperable with a detectorand a traversing mechanism for the detector: an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a signal to the vertical and horizontal deiiectionmeans in accordance with theV position of the detector; graded ltermeans mounted for interposition between the camera means and the screenfor effectively altering the spectral characteristic of the imageproduced by the camera means; means for positioning the filter means inaccordance with the activity of the detector; said oscilloscope having agating electrode for conv trolling its beam; first means for producingelectrical pulses at a frequency corresponding to the activity of saiddetector; second means for producing electrical pulses upon command;selectively operable means for operatively connecting said gatingelectrode to said first or second means.

9. In photographic color scanning apparatus cooperable with a detectorand a traversing mechanism for the detector: `an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means Iapplying a signal to the vertical and horizontaldeflection means in accordance with the position of the detector; gradedfilter means mounted for interposition between the camera means land thescreen for effectively altering the spectral characteristic of the imageproduced by the camera means; means for positioning the ilter means inaccordance with the activity of the detector; and means forsuperimposing a high frequency signal upon one of said deiiection meansfor widening the beam.

I0. In photographic color scanning apparatus coperable with a detectorand a traversing mechanism for the detector: an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a sign to the vertical and horizontal deflectionmeans in accordance with the position of the detector; adjustable biasmeans for producing signals for causing the oscilloscope beam to becentered on the screen when the detector is off center; adjustable meansfor scaling said signal applying means for adjusting image size inaccordance with the area scanned by said detector; graded filter meansmounted for interposition between the camera means and the screen foreffectively altering the spectral characteristic of the image producedby the camera means; means for positioning the filter means inaccordance with the activity of the detector; and means forsuperimposing 'a high frequency signal of adjustable amplitude upon oneof said deflection means for causing exposure in contiguous bands as thedetector traverses in one direction.

11. In photographic color scanning appartus cooperable with a detectorand a traversing mechanism for the detector: an oscilloscope having awide spectral emission screen; camera means for photographing thescreen; said oscilloscope having vertical and horizontal beam deflectionmeans; means applying a signal to the vertical and horizontal defiectionmeans in accordance with 4the position of the detector; graded filtermeans mounted for interposition between the camera means and the screenfor etTectively altering the spectral characteristic of the imageproduced by the carrera means; means for positioning the filter means inaccordance with the activity of the detector; means for producingelectrical pulses at a farequency corresponding to the ac-tivity of saiddetector; means for adjus-ting the width of said pulses; saidoscilloscope having a beam gating electrode operated by said pulses.

l2. In photographic color scanning appartus cooperable with a detector,a mechanism for causing the detector to traverse in a rectangularcordinate system, an analyzer and a rate meter operated by the detector:a cathode ray oscilloscope having a control grid, vertical andhorizontal beam deilection means, and a wide spectral emission screen; acamera for photographing the screen; an x potentiometer coupled to thedetector for producing an x signal in amplitude and polaritycorresponding to the deviation of the detector from a central positionalong the x axis; a y potentiometer coupled to the detector forproducing a y signal in amplitude and polarity corresponding to thedeviation of the detector from a central position along the y axis;means for applying the x signal to the horizontal defiection means;means for applying the y signal to the vertical deflection means;gradedfilter means mounted for interposition between the camera and thescreen for altering the spectral characteristic of the image produced bythe camera means; means for applying the analyzer signal to said controlgrid; and means for positioning the filter means in accordance with :theactivity of the rate meter.

13. In photographic color scanning apparatus cooperable with a detector,a mechanism for causing the detector to traverse in a rectangularcoordinate system, an analyzer and a rate meter operated by thedetector: a cathode ray oscilloscope having a control grid, vertical andhorizontal beam deflection means, and a wide spectral emission screen; acamera for photographing the screen; and x potentiometer coupled to thedetector for producing an x signal in amplitude and polaritycorresponding to the deviation of the detector from a central positionalong the x axis; a y potentiometer coupled to the detector forproducing a y signal in amplitude and polarity corresponding to thedeviation of the detector from a central position along the y axis;means for applying the x signal to the horizontal deflection means;means for applying the y signal to the vertical deiiection means;adjustable bias means for the vertical defiection means and thehorizontal deflection means for centering the beam on the screen whenthe detector is at an off center position; graded filter means mountedfor interposition between the camera and the screen for altering thespectral characteristic of the image produced by the camera means; meansfor applying the analyzer signal to said control grid; and means forpositioning the filter means in accordance with the activity of the ratemeter.

14. In photographic color scanning appara-tus cooperable with adetector, a mechanism for causing the detector to traverse in arectangular cordinate system, an analyzer and a rate meter operated bythe detector: a cathode ray oscilloscope having a control grid, verticaland horizontal beam deflection means, and a wide spectral emissionscreen; a camera for photographing the screen; an x potentiometercoupled to the detector for producing an x signal in amplitude andpolarity corresponding to the deviation of the detector from a centralposition along the x axis; a y potentiometer coupled to the detector forproducing a y signal in amplitude and polarity corresponding to thedeviation of the detector from a central position along the y axis;means for applying the x signal to t-he horizontal deflection means;means for applying the y signal to the vertical deflection means;adjustable means for scaling the x and y signals for adjusting imagesize in accordance with the area scanned by said detector; graded filtermeans mounted for interposition between the camera and the screen foraltering the spectral characteristic of the image produced by the camerameans; means for applying the analyzer signal to said control grid; andmeans for positioning the filter means in accordance with the activityof the rate meter.

15. In photographic colors scanning apparatus cooperable with adetector, a mechanism for causing the detector to traverse in arectangular coordinate system, an analyzer and a rate meter operated bythe detector: a cathode ray oscilloscope having a control grid, verticaland horizontal beam deflect-ion means, and a wide spectral emissionscreen; a camera for photographing the screen; an x potentiometercoupled to the detector for producing an x signal in amplitude andpolarity corresponding to the deviation of the detector from a centralposition along the x axis; a y potentiometer coupled to the detector forproducing a y signal in ampliture and polarity corresponding to thedeviation of the detector from a central position along the y axis;means for applying the x signal to the horizontal deflection means;means for applying the y signal to the vertical defiection means;adjustable bias means for t-he vertical deflection means and thehorizontal deflection means for centering the beam on the screen whenthe detector is at an ofir center position; adjustable means for scalingthe x and y signals for adjusting image size in accordnace with the areascarmed by said detector; graded filter means mounted for interpositionbetween the camera and the screen for altering the spectralcharacteristic of the image produced by the camera means; means forapplying the analyzer signal to said control grid; and means forpositioning the filter means in accordance with the activity of the ratemeter.

I6. In photographic color scanning apparatus cooperable with a detector,a mechanism for causing the detector to traverse in a rectangularcoordinate system, an analyzer and a rate meter operated by theedetector: a cathode ray oscilloscope having a control grid, verticaland horizontal beam deflection means, and a wide spectral emissionscreen; a camera for photographing the screen; an x potentiometercoupled to the detector for producing an x signal in amplitude andpolarity corresponding to the detector from a central position along thex axis; a y potentiometer coupled to the detector for producing a ysignal in amplitude and polarity corresponding to the deviat-ion of thedetector from a central position along the y axis; means for applyingthe x signal to the horizontal deflection means; means for applying they signal to the vertical deflection means; graded filter means mountedfor interposition between the camera and the screen for altering thespectral characteristic of t-he image produced by the camera means; aone shot square wave generator operated by said analyzer and in turnoperating said control grid; said one shot generator incorporatingadjustable means for determining the pulse width applied to said controlelectrode; and means for positioning the filter means in accordance withthe activity of the rate meter.

17. In photographic color scanning apparatus cooperable with a detector,a mechanism for causing the detector to traverse in a rectangularcoordinate system, an analyzer and a rate meter operated by theedetector: a cathode ray oscilloscope having a control grid, verticaland horizontal beam deiiection means, and a wide spectral emissionscreen; a camera for photographing t-he screen; an x potentiometercoupled to the detector for producing an x signal in amplitude andpolarity corresponding to the deviation of the detector from a centralposition along the x axis; a y potentiometer coupled to the detector forproducing a y signal in amplitude and polarity corresponding to thedeviation of the detector from a central position along the y axis;means for applying the x signal to the horizontal deiiection means;means for applying the y signal to the vertical deiiection means; gradedfilter means mounted for interposition between the camera and the screenfor altering the spectral characteristic of the image produced by thecarema means; a one shot square wave generator operated by said analyzerand in turn operat-ing said control grid; means selectively operable toapply pulses to said one shot generator on command and in place of saidanalyzer, including a selector switch and a condenser discharged uponmovement of said selector at which to one position; said one shotgenerator incorporating adjustable means for determining the pulse widthapplied to said control electrode; and means for positioning the filtermeans in accordance 'with the activity of the rate meter.

18. In photographic color scanning apparatus cooperable with a detector,a mechanism for causing the detector to traverse in a rectangularcoordinate system, an analyzer and a rate meter operated by thedetector: a cathode ray oscilloscope having a control grid, vertical andhorizontal beam deiiection means, and a wide spectral emission screen; acamera for photographing the'screen; an x potentiometer coupled to thedetector for producing an x signal in amplitude and polaritycorrespondmg to the deviation of the detector from a central positionalong the x axis; a y potentiometer coupled to the detector forproducing a y signal in amplitude and polarity corresponding to thedeviation of the detector from a central position along the y axis;means for applying the x signal to the horizontal deiiect-ion means;means for applying the y signal to the vertical deflection means; gradediilter means mounted for interposition between the camera and the screenfor altering the spectral characteristic of the image produced by thecamera means; adjustable bias means for the vertical deflection meansand the horizontal deflection means for centering the beam on the screenwhen the detector is at an oi center position; adjustable means forscaling the x and y signals for adjusting image size in accordance withthe area scanned by said detector; a one shot square wave generatoroperated by said analyzer and in turn operating said control grid; saidone shot generator incorporating adjustable means for determining t-hepulse width applied to said control electrode; and means for positioningthe filter means in accordance with the activity of the rate meter;means selectively oper- 'able to apply pulses to said one shot`generator on command and in place of said analyzer, including aselector switch and a condenser discharged upon movement of saidselector switch to one position.

19. In photographic color scanning apparatus cooperable with a detector,a mechanism for causing the detector to traverse in a rectangularcoordinate system, an analyzer and a rate meter operated =by thedetector: a cathode ray oscilloscope having a control grid, vertical andhorizontal beam deection means, and `a wide spectral emission screen; acamera for photographing the screen; an x potentiometer couplied to thedetector for produ-cing an x signal in amplitude and polaritycorresponding to the deviation of the detector from a central positionalong the x axis; .a y potentiometer couplied to the detector forproducing a y signal in amplitude and polarity corresponding to thedeviation of the detector from a central position along the y axis;means for applying the x signal to the horizontal deflection means;means for applying the y signal to the vertical deiiection means; gradediilter means mounted for interposition between the camera and the screenfor altering the spectral characteristic of the image produced by thecamera means; adjustable bias means for the vertical deflection meansand the horizontal deflection means for centering the beam on the screenwhen the detector is at an off center position; adjustable means forscaling the x and y signals for adjusting image size in accordance withthe area scanned by said detector; a one shot square wave generatoroperated by said analyzer and in turn operating .said control grid; saidone Shot generator incorporating adjustable means for determining thepulse width applied to said control electrode; means for positioning thelter means in accordance with the ac` tivity of the rate meter; meansselectively operable toapply pulses to said one shot generator oncommand and in place of said analyzer, including a selector switch and acondenser discharged upon movement of said selector switch to oneposition; and means for superimposing an adjustable high frequencysignal upon said vertical deflection means for causing exposure incontiguous lbands as the detector traverses in the x direction.

20. In photographic color scanning apparatus cooperable with a detectorand a traversing mechanism for the detector: an oscilloscope having awide spectral emission screen; camera means fixed with respect to theoscilloscope for photographing the screen; said oscilloscope having beamdeflection means controlling the position of the beam relative to saidscreen; means applying signals to the deection means in :accordance withthe position of the detector to cause the beam to assume a positionrelative to the screen corresponding to the position of the detector;and means having preselected color coded characteristics interposedbetween said screen and said camera means for changing the colorcharacteristic of the illumination spot in Iaccordance with the activityof the detector.

2i. In photographic color scanning apparatus as set forth in claim 20together with adjustable bias means for producing signals for causingthe oscilloscope beam to be centered on the screen when the detector isoff center.

22. In photographic color scanning -apparatus as set forth in claim 2@together with adjustable means for scaling the signal applying means foradjusting the image size in accordance with the area scanned by saiddetector.

23. In photographic coior scanning apparatus as set forth in claim 20together with adju-stable bias means for producing signals for causingthe oscilloscope beam to be centered on the screen when the detector isoi center; and adjustable means for scaling said signal aplying meansfor adjusting image size in accordance with the area scanned by saiddetector.

24. In photographic color scanning apparatus as set forth in claim 29together with means for producing electrical pulses at a frequencycorresponding to the activity of said detector; said oscilloscope havinga gating electrode for controlling said beam and operated by saidpuls-es.

25;){11 photographic color scanning apparatus as set forth in claim 2Gtogether with first mean-s for producing electrical pulses at afrequency corresponding to the activity of said detector; second meansfor producing electrical pulses upon command; `said oscilloscope havinga gating electrode for controlling its beam; and selectively operablemeans for operatively connecting said gating electrode to said iirst orsecond means.

26. In photographic color scanning apparatus as set forth in claim Ztitogether with means for superimposing a high frequency signal upon oneof said deflection means for widening the beam.

27. In photographic color scanning apparatus as set forth in claim 2@together with adjustable bias means for producing signals for causingthe oscilloscope beam to be centered on the screen when the detector isoff center;

13 14 adjustable means for scaling said signal applying means 2,638,4995/ 1953 Evans 88-24 for .adjusting image size in accordance with Ithearea 2,301,385 7 /1957 Rendell 3 52 131 scanned by said detector; andmeans for superimposing a 3 143 389 8/1964 Dranseld 346 109 highfrequency signal of adjustable amplitude upon one n of said deectionmeans for causing exposure in contigu- 3159744 12/1964 Stlcimey et al25o-7155 ous bands as the detector traverses in one direction. 3,241,4353/1966 Craig etal 88-24 References Cited by the Examiner RICHARD B.WILKINSON, Primary Examiner.

UNITED STATES PATENTS J. G. MURRAY, H. B. KATZ, Assistant Examiners.

2,373,114 4/1945 Goldsmith 352-131 10

1. IN PHOTOGRAPHIC COLOR SCANNING APPARATUS COOPERABLE WITH A DETECTORAND A TRAVERSING MECHANISM FOR THE DETECTOR: A HOLDER FOR APHOTOSENSITIVE SHEET; MEANS FIXED WITH RESPECT TO THE HOLDER FORPRODUCING A SPOT OF ILLUMINATION ON THE SHEET; MEANS COUPLED TO THEDETECTOR FOR CAUSING THE ILLUMINATION SPOT TO TRAVERSE RELATIVE TO THEPHOTOSENSITIVE SHEET IN ACCORDANCE WITH THE TRAVERSE OF SAID DETECTOR;AND MEANS HAVING PRESELECTED COLOR CODED CHARACTERISTICS INTERPOSEDBETWEEN THE ILLUMINATION PRODUCING MEANS AND THE HOLDER FOR CHANGING THECOLOR CHARACTERISTIC OF THE ILLUMINATIN SPOT IN ACCORDANCE WITH THEACTIVITY OF THE DETECTOR.